Development of New Neutral Beam Injection System on GOL-3 Facility

This paper presents prospect of now developed new 2 MW neutral beam injection system on GOL-3 facility. It discusses results of numerical simulation based on data from experiments on GOL-3. Vacuum environment in GOL-3 must be improved in order to reduce injected particles loss by charge exchange and fast ions cooling by peripheral plasma. Paper discusses some appropriate measures: long term gas pumping discharge, lithium suppression of gas recycling.